The table you are putting this on can not have a lip under it too close to the edge. The clamp needs to have flat space under the table to be tightened. I use the 36" arm on my 30" table. But, I have a spare 48" arm for tall dogs. Comes with a cheap groom loop, I recommend upgrading the groom loop to one I search groom loops on my site. If you have a tall dog, this is the one to go with.  All Sales Final.All Sales Final.